218 PROCEEDINGS OF THE ACADEMY OF [Feb., 



are kept up in this way, because the workers cannot retain the fertile 

 females in the nests by force, on account of the small size of the nests 

 and their position on vertical walls, or because the males may not often 

 be present simultaneously with the winged females? Would not 

 these dealated females be fecundated later by males appearing in the 

 same formicary? The fact remains that one often finds in Lcptothorax 

 nests dealated females with small abdomens and apparently not 

 fecundated, together with others obviously fertile. I refrain from de- 

 ciding the question." 



The questions asked by Forel so long ago still remain unanswered, 

 although it is clear that the colonies are not as a rule renewed and 

 maintained b}^ a retention of the virgin females in the parental nest. 

 My own observations show that the little colonies of these ants are 

 founded by single fertile females, in the very same manner as the huge 

 formicaries of Formica, Camponofus, etc. On several occasions I 

 have found dealated females of Lcptothorax either alone or with a 

 very few eggs, larvae or pupse in isolated oak-galls {e.g., L. obturator 

 q. v.). Moreover, I have never found more than one queen in a nest 

 in any of the species that I have taken, except at the very height of the 

 breeding season (May and early June in Texas, mid- or late summer in 

 the Northern States). Although in such nests I have sometimes seen 

 several dealated females, which probably arose as Forel has described, 

 I am inclined to believe that all of these, except the mother queen, 

 must soon leave the nest and establish colonies of their own. 



The question naturally suggests itself: Why are the colonies of 

 Lcptothorax so small? I believe that this peculiar condition may be 

 traced, in part at least, to the following causes, either singly or col- 

 lectively: 1. The females are but little larger than the Avorkers (in 

 L. Emcrsoni they are not even larger than the workers) and this 

 means relatively small fecundity. This appears to be the case also 

 in other ants that have females of the same or nearly the same size as 

 the workers (Myrmecina, Stcnamma s. str.; Ponerinae). And recipro- 

 cally, owing to this reduced fecundity, the cjueen cannot be abundantly 

 fed, since she produces but few workers. 2. The workers of Lcpto- 

 thorax are probably short-lived as compared with many other ants. 

 At least one is inclined to believe this from the rather high mortality 

 among these insects in artificial nests. 3. In most species of Lcpto- 

 thorax each colony contains only a single fertile queen.- 



^ Other observations on the habits of Lepiothorax will be found in the following 

 works: Adlerz, " Myrmecologiska Studier," II. Svenska Myror och deras Lef- 

 nadsforhollanden, Bihang till K. Sve7iska Vet. Akad. HandL, Bd. XI, No. 18, 



